The present invention relates to a method and system for developing traffic messages for broadcast, and more particularly to a method and system for compressing the data size of the traffic messages.
In some areas, systems broadcast data messages that contain up-to-the-minute reports of traffic and road condition information. These systems broadcast the traffic data over traffic message channels on a continuous, periodic, or frequently occurring basis. Traffic message receivers decode the data and provide up-to-the-minute reports of traffic and road conditions.
These traffic broadcast systems have several advantages over radio stations that simply broadcast audio traffic reports. For example, with the traffic broadcasting systems, a driver can obtain the traffic information quickly. The driver does not have to wait until the radio station broadcasts a traffic report. Another advantage of the traffic broadcast systems is that the driver does not have to listen to descriptions of traffic conditions for areas remote from his or her location. Another advantage of the traffic broadcast systems is that more detailed and possibly more up-to-date information can be provided.
One protocol for broadcasting traffic messages is the Traffic Message Channel (TMC), which is used in Europe, North America and elsewhere. In Europe TMC is broadcast as part of the Radio Data System (RDS) and North America TMC is broadcast as part of the Radio Broadcast Data System (RBDS). Essentially RDS and RBDS are identical. Another traffic broadcast system, named Vehicle Information and Communication System (“VICS”) Center, is used in Japan. Traffic and road condition information can also be transmitted using other protocols, such as Traffic Experts Protocol Group (TPEG) and on other broadcast bearers including Digital Audio Broadcasting (“DAB”), Digital Multimedia Broadcasting (“DMB”), Hybrid Digital Radio (“HD Radio”), Digital Radio Mondiale (DRM), satellite radio, and other protocols and radio systems, such as MSN-Direct.
In these systems, the traffic data messages conform to one or more pre-established specifications or formats. The traffic message receivers decode the traffic data messages using these pre-established specifications or formats. Once decoded, the traffic information may be presented to a user.
Although traffic broadcast systems provide many important features, there continues a need for new features and improvements. The collection, processing and transmission of traffic information are costly. One area for improvement is the efficiency of the transmission of the traffic messages. Because systems broadcast traffic data over channels on a continuous, periodic or frequently occurring basis, considerable broadcast resources and bandwidth are used. Thus, there is a need to accurately and efficiently compress the traffic messages for broadcast.